1927] Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo — 228 
Mysorella (?) multisulcata, (Bourguignat) 
Text Figure 20 
Bythinia. multisulcata Boureuienat, 1888, ‘Iconogr. Malacol. Tanganika,’ p. 11, 
Pl. 111, figs. 7 and 8; 1890, Ann. Sc. Nat. Zool., (7) X, p. 52, Pl. 111, figs. 7 and 8. E. ie 
Sen 1904, Proc. Malacol. Soc. London, VI, 2, p. 100. Ancry, 1907, Bull. Scientif. 
france et Belgique, (5) TX, (1906), p. 250. 
Lake Tanganyika: shores of Ubuari Peninsula, on the western side (type 
locality). 
Stappers dredged this curious, beautifully sculptured species off 
Uvira; in the bay. of Tembwe; in the bay of Kilewa; in the bay of 
Sumbu; and in 100 meters off the western shore between the mouth of 
the Moba and Lobozi Rivers. We have examined three of the speci- 
mens obtained by this collector and have figured one. 
| } Amnicolins : 
Operculum thin, wholly corneous, retractile some distance within the aperture, 
spiral, composed of rapidly enlarging whorls, with decidedly eccentric nucleus. The 
' shell varies from turreted or pupiform to globose or depressed. 
There is no cervical lobe. The central tooth of the radula has one or several 
basal denticles on each side. 
Two species of Amnicolinse which we have seen from. the south- 
eastern Belgian Congo appear to represent a new genus. Amnicola 
ciliata Gould, described from West Africa, must be placed in Potamo- 
pyrgus. In addition, a small number of Ethiopian species have been 
referred to Hydrobia; but in the absence of specimens, we are unable to 
decide whether they are true Amnicoline. 
PALUDESTRINA d’ woe 
Paludina subgenus Paludestrina p’ORBIGNY, 1840 (or 1839), ‘Voy. Amérique 
Mérid., Moll.,’ p. 381. Type: Helix acuta Draparnaud, one of the species originally 
inpladent and ‘desigaaied as type by Bourguignat ir in 1887 (‘Etudes Pet. Paludinidées,’ 
10). 
a Hydrobia Hartmann, 1821, ‘Syst. Erd u. Siisswasser Gasterop. Europa’ 8,’ in 
Sturm, ‘Deutschland’s Fauna,’ VI, 5, pp.47 and 58. Type: Helix acuta Draparnaud, 
as designated by Gray (1847, Proc. Zool. Soc. London, p. 151) (preoccupied by 
Hydrobius Leach, 1817). : 
Paludestina Gray, 1847, Proc. Zool. Soc. London, p. 151. Misspelling of Palud- 
estrina, as a synonym of Hydrobia. Type: Helix acuta Draparnaud. 
The members of this genus live in fresh or brackish water. The 
following African species appear referable to it. 
Paludestrina alabastrina (Morelet)=Hydrobia alabastrina Moreet, 1889 
Journ. de Conchyl., XX XVII,.p. 19, Pl. 1, fig. 5. Port Elizabeth, Cape Colony. 
Paludestrina (2) balfourt (Godednisnicten) = Hydrobia (?) balfourt GoDWIN- 
Austen, 1883, Proc. Zool. Soc. London, p. 4, Pl. 1, figs. 4-5. Sokotra. 
